By

Guerrero, Mexico - In Yolanda Gonzalez's dream she climbs out of bed, feeling dizzy in the heat of the night. Everybody else is sleeping, so she walks to the backyard, where everything is still, apart from the dogs that will not stop barking.

Her son, Jonas Trujillo, is sitting on a chair at the threshold of the house.

"I told him, 'You have arrived home', but he did not answer. He just looked serious, staring at me," she recalls.

She urges him to get inside the house, but all he does is stare at her.

"I hugged him," she says

Then he just begins to crumble, disappearing into the darkness.

In Yolanda's dream, her son is wearing a red striped T-shirt, jeans and sandals - the same clothes he wore on the day he left for college.

"I felt good that night," she says.

"But then I woke up and I did not see him at all."

Mothers of the disappeared

Before that night, Yolanda struggled to sleep at all. But now she goes to bed early every evening, just in case she should dream of him again.

During the days, though, she does not like to talk about her son. The only people she will discuss him with are the other mothers of the disappeared.

Jonas was one of the 43 students from a rural teachers' training college in Ayotzinapa, in the southwestern Mexican state of Guerrero, who went missing in the nearby city of Iguala on September 26, 2014.

About 100 students had commandeered buses to travel to Mexico City for a protest marking the killing of students in 1968. But police attacked the buses, killing at least six people, and arrested the students. Forty-three of them have not been seen since.

The government says that Iguala's mayor ordered the arrest of the students and, once they were in custody, the police handed them over to the Guerreros Unidos crime syndicate. Three gang members confessed to murdering the students and burning their bodies, but some have disputed this version of events - and exactly what happened to the students, and on whose orders, remains uncertain.

A painting at Ayotzinapa's teacher training college reads: 'Genaro Vazquez Rojas [a rebel leader] your fight was not in vain, the gun you left we took in our hands' [Eduardo Miranda/Al Jazeera]

'He was taken alive, we want him alive'

A meeting of the parents of the missing students has just come to a close. Mothers and fathers gather in small groups on the college's basketball court. They talk quietly; some shake their heads, others look at the floor. Yolanda sits on a bench and begins to talk.

"We still feel as though it happened just yesterday," she says.

Her hair is beginning to turn grey at the temples, her eyes are red from crying.

"Jonas decided to study here because we are peasants and he used to say, 'I don't want to work with my parents in the fields.'

"He wanted to study," she continues, taking a tissue from her bag to wipe away her tears and explaining how he was driven to study by a desire to help his family.

"I think the government is responsible; they handed them over to the police," Yolanda says. "They came here to study, what did they take them for? If they have done something wrong, they would remain in jail."

A canvas turtle, the symbol adopted by the parents in their struggle to find out what happened to their sons, looks down upon them from the roof of one of the classrooms. It sways in the wind.

At the desk that used to be Jonas' there is now a kite bearing his name and picture. "He is 20 years old, he is from Ticui, Guerrero. He was disappeared on 09-26-2014. He was taken alive, we want him alive," it reads.

Kites commemorate some of the missing students [Eduardo Miranda/Al Jazeera]

Going to college

Jonas Trujillo Gonzalez was born on March 29, 1994 - Saint Jonas' day - in Ticui, in the municipality of Atoyac de Alvarez, in the state of Guerrero.

"He enjoyed working because he liked earning money," his mother explains.

"He liked girls, he enjoyed being around them. He was smiley. A lot of kids used to hang out with him because he enjoyed goofing around and he was smiling all the time."

He was prone to unexpected fits of laughter, she remembers.

Jonas followed his brother, Benito, to the teacher training college. At first, his father was not happy about it, as he knew it meant that he would no longer be around to work in the fields, helping him to grow corn and sesame.

Before he left for college, Jonas gave his mother a black bracelet. She carries it with her everywhere.

Yolanda Gonzalez is still hopeful that her son will one day return [Eduardo Miranda/Al Jazeera]

Still waiting

It was five weeks after he left for college that Yolanda got a call from Benito. It was supposed to be him, not Jonas who attended the protest.

"I asked him, 'Haven't you seen Jonas?'," she says. "That was around 7.30pm.

"At around 8pm or 9pm, they called my daughter to say what had happened in Iguala."

Another of Jonas' brothers, Martin, tried to call him on his mobile phone. The first time he called, the phone rang. But after that it went straight to voice mail.

Yolanda's children tried to comfort her, assuring her that this sort of thing happened regularly - students were arrested and then released shortly after, they told her.

As Yolanda paced the backyard, Jonas' brothers headed to Iguala. She called her daughter, who told her: "We are waiting for the ones who managed to escape."

Yolanda headed to the school to wait there. She is still there, waiting, and hoping that her son will be returned to her.

When the college celebrated Christmas, Jonas' family left a message on the Christmas tree. "Jonas: Don't give up; your family is still waiting for you with arms wide open. We are sure that baby Jesus will do us the miracle of giving you back soon. We love you," it read.

A sign at the entrance to Atoyac, Guerrero, says its population is 60,000 [Alejandro Saldivar/Al Jazeera]

The poppy fields

Ticui is a small town with a population of 60,000 people, according to a sign at the town's entrance.

Few people here dare to talk about what happens on the edge of town, and most avoid going there.

It is a place that seems to resemble an unfinished sketch - a bush over here, a tree over there. Dogs the same colour as the dust roads prowl with their tongues hanging out.

This area is at the heart of Guerreros Unidos' operations and is often the scene of disputes between competing cartels.

In 2013, the army destroyed 718 poppy plantations, covering 151 hectares, and 42 marijuana plantations over 14 hectares, in an operation called Guerrero I-2013.

According to the office of Mexico's general attorney, one hectare of poppy flower can produce 24.2lb (11kg) of opium gum, from which 88 grams or 70,000 doses of heroin can be obtained.

Half a pound of opium costs roughly $1,818 at the country's northern border with the United States. And it is along the 54-mile highway between the Acapulco port and Atoyac that the cartels transport the opium gum in trucks.

With the cartels and their drug trade come murder and crime, and Guerrero has consistently had one of the highest murder rates in Mexico over recent years.

Martin shows a picture of his brother Jonas playing with a donkey [Eduardo Miranda/Al Jazeera]

Dreams of a brother

At Jonas' family home, everything is quiet. At the entrance, a red scooter waits for Jonas to return. Only 25-year-old Martin and the dogs are at home. Yolanda is still at the college, waiting. She has lived there since her son went missing. And Jonas' father is in Acapulco taking care of his mother.

Lizards dart across the blue walls of the house; two images of the Virgin of Guadalupe hang from one, guarded, it seems, by a golden dog called Loba.

Martin has just woken up. He says it was a dream that shook him from his sleep - a dream of his brother.

He often dreams of him, lying on a colourful hammock in the backyard. But when he wakes up, startled, Jonas is no longer there. Sometimes, when that happens, he picks up a bottle and drinks himself back to sleep again.

His mother told him not to speak to anybody, he says. "But I do want to talk," he adds.

He strokes Loba and says: "I don't remember him any more." Then he cannot continue. A knot forms in his throat and tears fill his eyes.

"My brother used to wear a cap every day," he says, picking a red one from a plastic table. He puts the cap on his head and then removes it again.

He tries to think of other things to say about his brother, but the thoughts will not form.

He takes out his phone and navigates through his digital family photo album, his finger touching his brother's face. There are pictures of Jonas playing with a donkey, Jonas smiling with friends, Jonas on a motorcycle, Jonas standing in a poppy field, holding a flower. He zooms in on a picture of Jonas smiling. Martin looks at it, or perhaps through it. "I drink every day since the day they took him," he says.